The neck contains several vital organs which are integral components of the respiratory, endocrine and gastrointestinal systems. Detailed knowledge of these organs is paramount to understanding the anatomy of the neck.
The pharynx is the tube-like chamber which connects the nasal and oral cavities to the oesophagus and larynx. It is composed of both circular and longitudinal muscle fibers that are innervated by its own pharyngeal plexus. The arterial supply to the pharynx is provided by branches of the external carotid artery, while the venous drainage enters the internal jugular vein. The pharynx is divided into three distinct sections – the nasopharynx, oropharynx and laryngopharynx.
The larynx is located in the proximal component of the respiratory tract and it is structurally based on a cartilaginous scaffold which is held together by membranes, ligaments and intrinsic muscles. The extrinsic muscles enable the larynx to move as a unit via their attachments to the hyoid bone. The vocal folds found within the larynx are mobile and provide the larynx with several important functions – including protection of the more distal respiratory tract, control of phonation and facilitation of coughing.
The oesophagus is the muscular tube which transports ingested food from the laryngopharynx to the stomach. The oesophagus is lined internally by non-keratinized stratified squamous epithelium, and its muscle layers are set in three different orientations so as to enable peristaltic contractions. The cricopharyngeus muscle forms an upper oesophageal sphincter, together with a functional lower oesophageal sphincter, which reduce air entry and gastric reflux.
The thyroid gland is located within the visceral compartment of the neck between the levels of C5 and T1, and is situated deep to the infrahyoid muscles. It comprises two broad lobes laterally, joined medially by a narrower isthmus. The thyroid is supplied with blood by both the superior and inferior thyroid arteries. The inferior thyroid arteries also provide the parathyroid glands – four small oval glands which are situated in pairs immediately beneath the lobes of the thyroid within its sheath.
In conclusion, it is important to note that the organs found in the neck play a vital role in the functioning of several systems. It is therefore important for healthcare professionals to understand the anatomy and function of these organs in order to provide the highest quality of care.
